Formation of Coal

1. Non-renewable fuels that formed long ago from the remains of plants and animals. Fossil Fuels: The origin of fossil fuels, starts with photosynthesis.Note that if the reaction runs in reverse, it produces energy and releases carbon dioxide and water. Formation of Coal Coal is considered a Fossil Fuel. Coal is an organic sedimentary rock which forms from the decaying of plant materials such as moss, ferns and parts of trees (dried out peat bogs). Reference: Tarbuck and Lutgens Pages 46

2. Coal is found in beds called seams, usually ranging in thickness from 0.5 to 3m, although someseams reach 30 m. Two major coal producing periods are known in geologic history. Duringthe Carboniferous and Permian Periods, the continents were apparently located near the equatorand covered by shallow seas. This type of environment favoured the growth of vegetation andrapid burial to produce coal. Coalis a sedimentary/metamorphic rock produced in swamps where there is a large-scaleaccumulation of organic matter from plants.Organic materials consist of carbon, oxygen, and hydrogen. When plant material is buried, the hydrogen and oxygen (H2O) is released leaving carbon. Formation of Coal

3. 1) Formation of Peat. Compaction of the peat due to burial drives off volatile components like water andmethane, eventually producing a black-colored, organic-rich coal called lignite . Swamps are areas where organic matter from plants accumulate. As the plants die and get buried they compact to becomepeat.With time and more compaction, almost all of the water is lost and three different grades of coal result. Soft brown coal which consist of about 40% carbon and do not burn efficiently. Peat Burial Burial 2) Formation of Lignite Coal. Compaction Lignite Coal Seam Formation of Coal The Formation of CoalInvolves Several Steps:

4. 3) Formation of Bituminous Coal. Soft coal which consist of about 85% carbon and burns readily but produces a lot of smoke. If the rockbecomes metamorphosed, a high grade coal called anthracite is produced. Hard dark coal which consist of 90% to 95% carbon and burns very hot and clean. Forms as a result of metamorphic conditions. Furthercompaction and heating results in a more carbon- rich coal called bituminouscoal. Anthracite coal produces the most energy when burned. Compaction Bituminous 4) Formation of Anthracite Coal. Metamorphism Burial Burial Anthracite Coal Seam Formation of Coal The Formation of CoalInvolves Several Steps:

5. Sample Problem Use a diagram to explain the four stages involved in the formation of anthracite coal. Answer: From peat to lignite there is burial and compaction. From lignite to bituminous there is greater burial. From bituminous to anthracite there is metamorphism. Water and gases are releasedduring all stages.